The Inhibitory Effect Of BBI608 Derivative LD-17 On The Lung Cancer Cells

Objective: Lung cancer is one of the most common malignancies,and its incidence and mortality have remained high,rising year by year.Lung cancer can be divided into two categories: small cell lung cancer(SCLC)and non-small cell lung cancer(NSCLC),of which non-small cell lung cancer accounts for the vast majority.At present,the main treatments for lung cancer include surgery,chemotherapy,radiotherapy,immunotherapy,and targeted therapy.However,most patients have lost the opportunity for surgery when they were diagnosed,the survival rate is low,and the prognosis is poor.The main obstacles and large side effects of radiotherapy seriously affect the life quality of patients.Molecularly targeted drugs have high selectivity for diseased tissues,and light adverse reactions.Therefore,clarifying the pathogenesis of lung cancer and finding new molecular targeted drugs have become the development trend of lung cancer treatment.The composition of tumors is heterogeneous.Cancer stem cells(CSC)are a small subpopulation with self-renewal and differentiation capabilities,tumorigenicity in transplanted animal hosts,and resistance to chemoradiation.These factors result in resistance to traditional therapies of lung cancer.Therefore,targeted preparation of cancer stem cells can improve the therapeutic effect of tumors.Signal transducer and activator of transcription 3(STAT3)is an oncogene that is transiently activated and phosphorylated into the activated form of STAT3(p-STAT3)in normal cells,playing dual roles of cell signal transduction and activation of transcription It is highly expressed and continuously activated in a variety of cancer tissues,promotes tumor stem cell-mediated proliferation,and inhibits apoptosis.In addition,STAT3 plays an important role in various pathological processes such as promoting angiogenesis,enhancing immune tolerance and inducing inflammation.Therefore,STAT3 can be used as a site of targeted drugs for the treatment of lung cancer.BBI608(Napabucasin)is the first oral small molecule inhibitor that inhibits cancer stem cell activity by targeted binding to STAT3.Studies have shown that BBI608 alone and in combination has strong antitumor recurrence and metastasis activity in vivo and in vitro,and has no pharmacokinetic interaction with other drugs,with less side effects.According to reports,only a small number of patients have adverse gastrointestinal reactions after taking the drug.The FDA have approved BBI608 for the treatment of gastric or esophageal junction cancer and pancreatic cancer.Studies have shown that BBI608 is effective in early clinical trials such as liver cancer,colon cancer,ovarian cancer,non-small cell lung cancer and glioma.In the development of new drugs,in order to further optimize the activity of existing antitumor compounds,they are usually used as lead compounds for structural modification to synthesize a series of derivatives,from which compounds with better activity and selectivity are selected for further research,so that we have the opportunity to get new antitumor drugs with the same or different mechanism of antitumor.Based on this,this subject intends to study the inhibitory effect of BBI608 derivative LD-17 on lung cancer cells and explore its possible mechanism.Methods: Lung cancer cells A549,NCI-H460 and normal lung cells MRC-5 were cultured.The inhibitory effect of BBI608 and its derivative LD-17 on lung cancer cells A549,H460 and normal lung cells MRC-5 was detected by CCK-8 method.Annexin V / PI double staining flow cytometry was used to detect the apoptosis effect of BBI608 and its derivative LD-17 on lung cancer cells.The effects of BBI608 and its derivative LD-17 on the phosphorylation level of target gene STAT3 and the expression of apoptosis-related proteins Bcl-2 and Bax were detected by Western blot.Results:1.The results of CCK-8 showed that BBI608 and its derivative LD-17 had significant inhibitory effects on the proliferation of lung cancer cells A549 and H460,and as the concentration and time increase,the inhibitory effect increases.2.Annexin V / PI double staining flow cytometry results showed that different concentrations of BBI608 and its derivative LD-17 can induce apoptosis of lung cancer cells A549 and H460.3.Western blot results showed that BBI608 and its derivative LD-17 can reduce the level of p-STAT3 in lung cancer cells A549 and H460,.4.Western blot results showed that BBI608 and its derivative LD-17 can reduce the expression of Bcl-2 protein in lung cancer cells A549 and H460,and increase the expression of Bax protein.Conclusion:1.BBI608 and its derivative LD-17 can inhibit the proliferation of lung cancer cells A549 and H460,as the concentration and time increase,the inhibitory effect increases.And selectivity of LD-17 to lung cancer cells is significantly higher than that of BBI608.2.BBI608 and its derivative LD-17 down-regulate the expression of Bcl-2 by inhibiting the phosphorylation of STAT3,while increasing the expression of Bax,and promoting the apoptosis of lung cancer cells A549 and H460.